3 files changed, 179 insertions, 0 deletions
diff --git a/lib/private/KnownUser/KnownUser.php b/lib/private/KnownUser/KnownUser.php
new file mode 100644
index 00000000000..808c0400c6e
--- /dev/null
+++ b/lib/private/KnownUser/KnownUser.php
@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OC\KnownUser;
+
+use OCP\AppFramework\Db\Entity;
+
+/**
+ * @method void setKnownTo(string $knownTo)
+ * @method string getKnownTo()
+ * @method void setKnownUser(string $knownUser)
+ * @method string getKnownUser()
+ */
+class KnownUser extends Entity {
+	/** @var string */
+	protected $knownTo;
+
+	/** @var string */
+	protected $knownUser;
+
+	public function __construct() {
+		$this->addType('knownTo', 'string');
+		$this->addType('knownUser', 'string');
+	}
+}
diff --git a/lib/private/KnownUser/KnownUserMapper.php b/lib/private/KnownUser/KnownUserMapper.php
new file mode 100644
index 00000000000..4c3bbb0b436
--- /dev/null
+++ b/lib/private/KnownUser/KnownUserMapper.php
@@ -0,0 +1,73 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OC\KnownUser;
+
+use OCP\AppFramework\Db\QBMapper;
+use OCP\IDBConnection;
+
+/**
+ * @method KnownUser mapRowToEntity(array $row)
+ *
+ * @template-extends QBMapper<KnownUser>
+ */
+class KnownUserMapper extends QBMapper {
+	/**
+	 * @param IDBConnection $db
+	 */
+	public function __construct(IDBConnection $db) {
+		parent::__construct($db, 'known_users', KnownUser::class);
+	}
+
+	/**
+	 * @param string $knownTo
+	 * @return int Number of deleted entities
+	 */
+	public function deleteKnownTo(string $knownTo): int {
+		$query = $this->db->getQueryBuilder();
+		$query->delete($this->getTableName())
+			->where($query->expr()->eq('known_to', $query->createNamedParameter($knownTo)));
+
+		return $query->executeStatement();
+	}
+
+	/**
+	 * @param string $knownUser
+	 * @return int Number of deleted entities
+	 */
+	public function deleteKnownUser(string $knownUser): int {
+		$query = $this->db->getQueryBuilder();
+		$query->delete($this->getTableName())
+			->where($query->expr()->eq('known_user', $query->createNamedParameter($knownUser)));
+
+		return $query->executeStatement();
+	}
+
+	/**
+	 * Returns all "known users" for the given "known to" user
+	 *
+	 * @param string $knownTo
+	 * @return KnownUser[]
+	 */
+	public function getKnownUsers(string $knownTo): array {
+		$query = $this->db->getQueryBuilder();
+		$query->select('*')
+			->from($this->getTableName())
+			->where($query->expr()->eq('known_to', $query->createNamedParameter($knownTo)));
+
+		return $this->findEntities($query);
+	}
+
+	public function createKnownUserFromRow(array $row): KnownUser {
+		return $this->mapRowToEntity([
+			'id' => $row['s_id'],
+			'known_to' => $row['known_to'],
+			'known_user' => $row['known_user'],
+		]);
+	}
+}
diff --git a/lib/private/KnownUser/KnownUserService.php b/lib/private/KnownUser/KnownUserService.php
new file mode 100644
index 00000000000..cd257cf1b12
--- /dev/null
+++ b/lib/private/KnownUser/KnownUserService.php
@@ -0,0 +1,76 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2021 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OC\KnownUser;
+
+class KnownUserService {
+	/** @var KnownUserMapper */
+	protected $mapper;
+	/** @var array */
+	protected $knownUsers = [];
+
+	public function __construct(KnownUserMapper $mapper) {
+		$this->mapper = $mapper;
+	}
+
+	/**
+	 * Delete all matches where the given user is the owner of the phonebook
+	 *
+	 * @param string $knownTo
+	 * @return int Number of deleted matches
+	 */
+	public function deleteKnownTo(string $knownTo): int {
+		return $this->mapper->deleteKnownTo($knownTo);
+	}
+
+	/**
+	 * Delete all matches where the given user is the one in the phonebook
+	 *
+	 * @param string $contactUserId
+	 * @return int Number of deleted matches
+	 */
+	public function deleteByContactUserId(string $contactUserId): int {
+		return $this->mapper->deleteKnownUser($contactUserId);
+	}
+
+	/**
+	 * Store a match because $knownTo has $contactUserId in their phonebook
+	 *
+	 * @param string $knownTo User id of the owner of the phonebook
+	 * @param string $contactUserId User id of the contact in the phonebook
+	 */
+	public function storeIsKnownToUser(string $knownTo, string $contactUserId): void {
+		$entity = new KnownUser();
+		$entity->setKnownTo($knownTo);
+		$entity->setKnownUser($contactUserId);
+		$this->mapper->insert($entity);
+	}
+
+	/**
+	 * Check if $contactUserId is in the phonebook of $knownTo
+	 *
+	 * @param string $knownTo User id of the owner of the phonebook
+	 * @param string $contactUserId User id of the contact in the phonebook
+	 * @return bool
+	 */
+	public function isKnownToUser(string $knownTo, string $contactUserId): bool {
+		if ($knownTo === $contactUserId) {
+			return true;
+		}
+
+		if (!isset($this->knownUsers[$knownTo])) {
+			$entities = $this->mapper->getKnownUsers($knownTo);
+			$this->knownUsers[$knownTo] = [];
+			foreach ($entities as $entity) {
+				$this->knownUsers[$knownTo][$entity->getKnownUser()] = true;
+			}
+		}
+
+		return isset($this->knownUsers[$knownTo][$contactUserId]);
+	}
+}